Portable communication devices (e.g., smart phones and smart watches) are becoming increasingly waterproof by implementing electronic components inside sealed enclosures. However, certain components such as environmental (e.g., pressure, temperature and humidity) sensors, gas sensors, particulate matter (PM) sensors, speakers and microphones rely on physical interaction with the external environment for proper functionality. The physical interaction can be through a small opening provided on the enclosure. Exposure to the environmental aggressors such as fresh and salt water, skin oil, dust, sunscreens can cause a variety of system integration problems.
Port occlusion by water or debris is among the most severe problems, which can result in degradation in user experience, poor device reliability and/or device misreading. As an example, the accuracy of pressure sensors can be greatly reduced when residual water occludes the sensor surface, resulting in misreading to detect external pressure changes. As the water evaporates (which can take hours), false pressure-change signals can be detected. For example, when pressure is sensed for measuring height to count the number of stairs climbed by a user, the false pressure-change signals can indicate false or missed flight of stairs, which degrades the user experience.